The Clinical Trials Core assures uniform, highly effective treatment of patients with acute leukemia, providing an appropriate setting for evaluation of the clinical relevance of new information coming from the research projects and the Central Laboratory Core. Highly experienced clinical investigators are available to participate in the design of clinical trials working together with laboratory investigators in the projects. Expert data management and secretarial personnel assure that data generated from the clinical trials are collected in a timely way and entered into the computer to facilitate analyses and regular reporting of results.